1sec .. 99hr timer on Arduino

  Indication - 2-digit LED, time is displayed in 4 modes:
- "SS" - seconds (1..59),
- "M.S" - minutes + tens of seconds (1.0..9.5),
- "MM." - minutes (10..59),
- "H.H." - hours (1..99).

  Control - by 3 keys: "+", "-", "Start/Stop".
  Beeper starts to beep 10 sec before timer expires, and at the end.
  Load control - via optotriac on A0 line.

Project